Agreed. I've been running KDE 4.8 on FC16 at home for the last 2 weeks or so. Very happy with it.
Thanks, that's good to know. I'll make a point of giving it a "spin" so to speak, so I can be confident to recommend it alongside the others I mentioned. I really should anyway since there's many a package on our build service (openSUSE) using fc15/16 as build targets.
Folks from the KDE team have also popped up on the distro's board of directors and engineering committes, which are voted offices. And Red Hat has several paid employees working on KDE/Qt stuff at least part-time.
Fans of KDE definitely shouldn't dismiss Fedora automatically anymore, especially if they otherwise have a strong appetite for Fedora's usual virtues (closeness to upstream, package freshness). It's a really good KDE binary distro these days.
(Disclaimer: I'm a KDE developer, but KDE of course remains highly committed to distro neutrality, i.e. the above are my personal views as a Fedora user, not as a representative of KDE. And I'm not involved with Fedora development.)